"After she called him a racist and misogynist, a xenophobic, I don't know, schizophrenic, and I don't know what else she called him at the end of that debate, I think it's fair game," the former New York City mayor and Trump supporter told CNN's Jake Tapper on "State of the Union" Sunday.

Without evidence, Trump said at a rally Saturday: "I don't even think she's loyal to Bill, if you want to know the truth. And really folks, really, why should she be?"

In the contentious interview, Giuliani often tried to shift to attacks on Clinton, while Tapper pushed him to directly address Trump's unfounded claims made Saturday.

"The reason you can't defend this line of attack is because it's indefensible," Tapper said.

Eventually, Giuliani said: "That was a sarcastic remark pointing out that Bill Clinton has, you know, quite a past, and Hillary Clinton has done quite a job on attacking the people who were victims of Bill Clinton."

Both Trump and Giuliani have been married three times, with some ending in divorces amid reports of affairs.

Pressed on whether anyone in Trump's camp should be criticizing others' marriages, Giuliani said: "It isn't her marriage. It's the way she goes on the attack and tries to hurt victims of sexual predations."

"I am saying, the problem with Hillary Clinton has nothing to do, as far as I'm concerned, with her marriage," Giuliani said. "It's her protection of Bill Clinton for 20 or 25 years against allegations of rape, taking advantage of an intern, and going on the attack and trying to make those women appear to be insane in some cases."